Folks can feel free to look at my private sblock to Gansk on this. I don't know if Fang would only fail his SV versus Shimmy's breath on a '1', but it was starting to feel that way. It looked like Shimmy couldn't dare face him in close combat, even invisible and with true-sight to pierce the mirror images - but knocking 8 off of Fang's strength could have shifted those odds. The spell turning effect meant that Shimmy couldn't debuff Fang, and offensive spells were unlikely due to the usual dragon CL vs. SR issues.
So if Shimmy did nothing but fly around, he'd need to get missed 5 times in a row. He gets 50% change on each pass thanks to invisibility, but that means each 5-round period only has a 3% chance of causing the draw. Actually better than that since sometimes Fang would get through invis but still miss due to AC, but even if we say AC frustrates him a quarter of the times he gets through that's less than than 10% per 5-round period.
So, could Fang's hits take him down in 100 rounds, given Shimmy's cure moderate ability? Would Fang finally succumb to the weakness gas that he'd be subjected to every 2-3 rounds?
Bottom line is that it would have been a long time, made even longer by my long delays between posts.
In any case, I'll keep looking in to see how the arena is going. I'm still interested in the ToC, but don't want to subject people to wait on my posts.